Generate wrapper binding functions for non-identifier imports

This change should ensure performance.now() and document.foo() does not
break.

Author: CountBleck

Diff for: src/bindings/js.ts

@@ -285,7 +285,7 @@ export class JSBuilder extends ExportsWalker {
       sb.push(escapeString(name, CharCode.DoubleQuote));
       sb.push("\"");
     }
-    if (isPlainFunction(signature, Mode.Import) && !code) {
+    if (isPlainFunction(signature, Mode.Import) && !code && isIdentifier(name)) {
       sb.push(": (\n");
       indent(sb, this.indentLevel + 1);
       sb.push("// ");